Scoop for an implement



Oct. 9, 1962 c. E. WREN ETAL 3,057,495

SCOOP FOR AN IMPLEMENT Filed July 14, 1958 5 Sheets-Sheet 1 INVENTORSCLYDE E. WREN HENRY DANUSER MM, M

ATTORNEYS Oct. 9, 1962 c. WREN ETAL 3,057,495

SCOOP FOR AN IMPLEMENT Filed July 14, 1958 3 Sheets-Sheet 2 INVENTORSYDE E. WREN NRY DANUSER 64m M47 Mee ATTORNEYS Oct. 9, 1962 c. E. WRENETAL 3,057,495

SCOOP FOR AN IMPLEMENT Filed July 14, 1958 s Sheets-Sheet s 7O 75 8O 7666 65 25 L W i 73; T 1 I V r I M FIG. 5

4] CLYDE E. WREN HENRY DANUSER 3o 11 BY v 3 M4, M [Qty-(Le FIG. 4

:ATTORNEYS This invention relates generally to improvements in a scoopfor an implement, and more particularly to improved control mechanismfor moving and retaining the bucket in various desired positions.

It is an important objective to provide a control means operativelyinterconnecting the stop means for retaining the bucket and the valvemeans for controlling operation of the hydraulic system incident torotating the bucket to the different positions, so that the stop meansis operated in response to the valve means.

An important object is achieved by the improved mechanisminterconnecting the stop means and the valve means of the assemblypreviously described.

Another important objective is to provide a valve means that operates ahydraulic means to rotate the bucket in a predetermined sequence tovarious positions, and that includes means for actuating a pair of pinshydraulically in response to mechanism actuating the hydraulic meanswhich causes operative engagement of stop members selectively with stopabutments on the bucket in the different positions.

Still another important objective is realized by the provision of a rockshaft rotatively mounted on the scoop frame alongside of the bucket, theshaft having means interconnecting the valve means and having stop meansadapted to engage the periphery of the bucket and selectively to engagestop abutments upon actuation of the shaft responsively to operation ofthe valve means.

Yet another important object is to provide an implement scoop that issimple and durable in construction, economical to manufacture, efficientin operation and capable of ready operation by anyone.

The foregoing and numerous other objects and advantages of the inventionwill more clearly appear from the following detailed description of apreferred embodiment, particularly when considered in connection withthe accompanying drawings, in which:

FIG. 1 is a perspective view of the implement scoop;

FIG. 2 is a schematic drawing of the hydraulic system and the controlmechanism connecting such system to the bucket;

FIG. 3 is a cross sectional view of the sequence valve;

FIG. 4 is an enlarged cross sectional view of the top portion of thehydraulic cylinder shown at the left in FIG. 2, and

FIG. 5 is an enlarged cross sectional view of the top portion of theright hand cylinder shown in FIG. 2,

Referring now by characters of reference to the drawings, and first toFIG. 1, it is seen that the implement scoop includes a frame generallyindicated at 113 having end members 11 interconnected and attached bytubular brace 12 extending therebetween. Rotatively mounted at journals13 on end frame members 11 is a bucket referred to at 14. A bracket 15is fastened to the cen ter of tubular frame brace 12 and is adapted tobe attached to the hydraulic lift mechanism of a conventional tractor orlike implement.

The bucket 14 consists of an elongate trough member 16 closed atopposite ends by plates 17 that are journalled at 13 to the end framemembers 11.

The hydraulic system of the operating tractor or prime mover must have apump 20 shown in the schematic drawing of FIG. 2, and a normal controlvalve 21 capable of directing a flow of oil through either of the flowlines 3,357,495. Patented Oct. 9, 1952 22 and 23 leading to thehydraulic system of the scoop. These flow lines 22--23 are connected toa sequence valve 24, the details of which are disclosed in FIG. 3. Thesequence valve 24 is operatively connected by lines 25 and 26 tohydraulic cylinders indicated at 27 and 28.

The cylinders 27 and 28 are pivotally attached to the end frame members11 by pivot bolts 18. The end frame members 11 each have a horizontalportion provided with an aperture 29 through which a cylinder 27 or 28extends, such aperture 29 being of a size to permit pivotal move ment ofthe cylinder therein.

The piston 30 of hydraulic cylinder 27 is pivotally attached at 31 to aplate 32 fixed to the bucket end plate 17. Similarly, the piston 33 ofhydraulic cylinder 28 is pivotally attached at 34 to plate 35 attachedto the opposite bucket end plate 17. It will be noted that the cylinders27 :and 28 are operatively connected to the bucket 14 so that thepistons 3i and 33 respectively act on opposite sides of the bucket pivotaxis 13 so as to give the effect of a double-acting cylinder.

Rotatively mounted on and between the end frame members 11 is atransverse rock shaft 36. As will be seen from FIGS. 1 and 2, the shaft36 is journalled in the housing of sequence valve 24, the shaftextending longitudinally of bucket 14 to the opposite end frame members11.

Fixed on each end of shaft 36 is a stop member 37 consisting of aU-shaped arm having a pair of rollers 40 and 41 adapted to engage theperiphery of the adjacent end bucket plate 17.

Each of the end bucket plates 17 is provided with three stop abutmentsindicated in FIG. 2 and referred to hereinafter in the terminology ofthe position of the bucket which :they determine, such as load stopabutment 42, carry stop abutment 43 and dump stop abutment 44. Thecooperation and coaction of the stop abutments 42-44 inclusive with thestop members 37 will be described in detail subsequently.

Located Within the housing of sequence valve 24 and attached to the rockshaft 36 is a valve follower 45 consisting .of a U-shaped member havinga pair of rollers 46 and 47. A pair of slide pins 50 and 51 are mountedin the sequence valve 24 and are operatively intercounected and actuatedby valve 24 in a manner subsequently described, the slide pins 50 and 51engaging the rollers 46 and 47 respectively of the valve follower 45 soas to rotate the shaft 36 in response to operation of sequence valve 24,and hence cause actuation of the stop members 37. The sequence valve 24coordinates the movement of the bucket stop members 37 with bucketmovements caused by the hydraulic cylinders 27 and 28, or with cylindermovements caused by external forces acting on the bucket 14, provides acertain amount of automatic bucket position control, and provides abucket locking feature.

The bucket control cylinders 27 and 28 are shown with their head endsgreatly expanded in FIGS. 4 and 5 to show the detailed construction.Each cylinder has a stepped throttling plug 52 and 53 respectivelyextending down from the head. These plugs 52-53 are engaged by rings 54and 55 respectively on the ends of the pistons 31 and 33 to obtain abraking action as the bucket rotates toward positive mechanical stops(not shown). Because the bucket 14 can be removed from the pivotbrackets to which it and the cylinders attach, and reversed for somespecial conditions, the functions of the cylinders are interchanged.

In order to adjust for this condition, throttling plug 52 has two lands56 and 57, while plug 53 has lands on and 61.

The cylinder 27 is provided with a passage 62 downwardly through thecenter of plug 52 communicating with 3 line 25, is provided with apassage 63 in plug 52 communicating with the interior of the cylinderbetween the plug lands 5657, and is provided with another passage 64communicating with feed line 25 and with the interior of the cylinderabove the plug land 56.

A valve member 65 is provided between the passage 63 and feed line '25,the valve member 65 being attached to a screw 66 to permit adjustment. Avalve member 67 and coacting valve ball 68 is disposed in passage 64. Ascrew 70 is attached to pin 67 to enable adjustment.

The cylinder 28 is provided with a passage 71 extending downwardlythrough plug 53 and opening at its bottom, the passage 71 communicatingwith the feed line 26. Another passage 72 places the feed line 26 incommunication with the interior of the cylinder above the plug land 60.Another passage 73 places the feed line 26 in communication with theinterior of the cylinder at the region between the plug lands 60 and 61.Another passage 74 places passage 73 in communication with the interiorof the cylinder above the plug land 60.

A screW-pin-ball valve combination 75 is disposed in passage 72 tocontrol flow therethrough. A similar screwpin-ball valve combination 76is disposed in passage 73 between the feed line 26 to control flowthrough passage 73. Another screw-valve member 77 is disposed betweenpassages 73 and 74 to control flow through passage 74.

In the schematic view of FIG. 2, the left hand view of both bucket endplates 17 is shown. In normal operation, the bucket will be movingtoward the left relative to the surface on which it is working and thereaction of both the material being loaded and the material in thebucket will tend to cause counterclockwies rotation of the bucket. Toprevent unwanted rotation, in various desired positions, the three stopabutments 4243-44 are provided at three points on the periphery of thebucket.

When the rear stop roller 41 is contacting the load stop abutment 42 asis shown, the bucket is in the correct position to gather a load ofmaterial. When rear stop roller 41 is positioned against the carry-stopabutment 43, the bucket is tipped up so that a greater bulk of loosematerial can be retained. If scarifier teeth 78 (FIG. I) are attached,such teeth will penetrate the ground when the bucket is lowered. Whenthe front stop roller 40 is positioned against the dump-stop abutment44, the bucket is in a position such that all material will fall fromit.

Fixed stops (not shown) provided between the frame 10 and the bucket 14prevent the bucket from rotating counterclockwise past the dumpingposition or clockwise past the carrying position.

For normal forward operation, the cylinder adjusting screws are adjustedso that valve member 65 is open, valve member 68 is open slightly butwill greatly restrict oil flowing upwardly through it, valve member 76is open to the point that there is only a slight spring force on theball 80 to restrict the oil flow, valve member 77 is open but alsorestricts oil flow, and valve member 75 is open to the point where thereis only slight spring force on ball 81 to restrict the oil flow.

The drawings of FIGS. 2, 3, 4 and show all parts of the hydraulic systemin the position they would assume when the bucket is rotated clockwiseinto loading position and the roller 41 is moving just past stopabutment 42. Oil flows from the pump 20 through the valve 21, throughline 22 and into the sequence valve 24. As a result, pressure is exertedthrough restriction 82 to the upper end of spool 83 slidably mounted inthe sequence valve 24, and is exerted on both sides of valve ball 84 andagainst valve ball 85. When the spool 83 is located in its lowermostposition as shown in FIG. 3, the reduced upper portion of spool 83places one side of the valve ball 85 and both sides of valve ball 84 incommunication with the restriction 82, that is in turn in communicationwith line 22.

In addition, pressure from line 22 is exerted through passage 86 andpast the valve 87 at a slightly reduced value to the side of valvemember 88 by way of passage 90. This same slightly reduced pressure istransmitted to the lower end of spool 83 through passage 91 com-,

municating with passage 90. Because of gravity and slightly lowerpressure at the bottom end, the spool 83 stays down in its lowermostposition as shown in FIG. 3. In this position, the passage is placed incommunication with the passage 86 and hence passage 22 by the annularrecess 92.

The oil flows down through line 22, through port 93, by the reducedvalve portion 94 formed in valve member 88, through port 95, and hencethrough line 96. It will be particularly noted and understood thatpassage 96 is not connected to slide pins 50 and 51 in any way.

Passage 97, in communication with passage 96, is placed in communicationwith cylinder line 26 by valve pin 98 and valve ball 100. Screw 101 isprovided to effect adjustment of the valve means 98100. The oil flowsfrom passage 96 through passage 97, causing the valve pin 98 to raiseand open valve ball 100. When the valve pin is raised, it seats againsta valve seat and stops flow from passage 97, and maintains the valveball in an open position. Valves 102 and 103 are safety valves only, andnever operate except when the system is overloaded.

As stated previously, the oil flows through passage 96 to the cylinderline 25, and hence passes to the cylinder 27. From FIG. 4, it is seenthat the oil pressure closes the valve ball 68 and the oil flows throughpassages 62 and 63 to cause the piston 30 to extend and rotate thebucket clockwise as seen in FIG. 2.

Clockwise rotation of bucket 14 causes a retraction of piston 33 ofcylinder 28, and thus causes a return flow through passages 71 and 72past valve ball 81. It Will be noted that the valve ball 80 preventsreturn flow upwardly through passages 73 and 74 as seen in FIG. 5. Thisreturn oil flows through line 26 into the sequence valve 24 past thevalve ball 100 (held in an open position by pressure on valve pin 98),and hence flows into passage 104 and is discharged into the sump throughline 23.

A small amount of pressure caused by fiow friction is exerted againstvalve ball 85, the upper side of valve member 88 through port 105, theleft end of valve member 88 through port 106, and the lower side ofvalve member 88 through the port and restriction 107. However, thispressure is too slight to cause any effect at these points.

Oil that is under pressure in line 22 flows through restriction 108 andexerts force against the slide pin 50 causing it to move to the right asshown in FIG. 3, to rotate the valve follower 45 clockwise, and hencecausing the stop roller 41 to move down into the depression 110 (FIG.2). The only purpose of the restriction at passage 108 is to restrictoil flow to and from the slide pin 50 and so damp any rapid andundesirable reciprocation of the slide pin 50 and oscillation of thevalve follower 45 and of rollers 40-41. The depressions 110 and 111(FIG. 2) are considerably deeper and allow stop roller 41 to dropfarther and allow follower 45 to rotate farther than any other points onthe bucket periphery contacted by the stop rollers 40-41.

This additional travel of stop roller 31 allows slide pin 50 to move tothe right (FIG. 3) forcing slide pin 51 and valve member 88 to theextreme left end of the bore in which the valve member 88 operates. Inthis position, the valve member '88 closes ports 93 and 95, and opensports 105, 107 and 113 to the common groove 94 provided in valve member88. Further, the spring 114 is compressed. The restriction at port 107is such that sufficient pressure is maintained in line 22 and at port112 to force valve member 88 far enough to the left to keep portpractically fully open.

This action of valve member 88 stops the flow of oil through passage 96to the cylinder 27, releases the valve pin 98 allowing the valve ball100 to close and hence stop the oil flow from cylinder 28, and stops thebucket 14 in the loading position.

The entire oil flow through line 22 is now passing through port 113 toport 135, through passage 104 andv hence back to the sump through line23. The only exception is a small amount or" oil passing from line 22through valve member 87, to port 112, through the small passage 115 invalve member 88, through port 106 back to the sump, and a small amountof oil passing through port 107 and back to the sump.

This condition will continue to exist as long as there is oil flowingthrough line 22 because any tendency of movement of valve member 83 tothe right because of spring 114 will restrict oil flow through port 105,increase pressure in line 22 through valve 87 to the port 112, and thustends to move the valve member 88 to the left, reestablishing theoriginal condition.

The events just described automatically stop the scoop bucket 14 in thecorrect position to load and so relieve the operator, who energizes thehydraulic system to return the bucket from dumping position to loadingposition, of the responsibility of stopping the bucket at the correctposition.

At this point it is assumed that the operator, seeing that the bucket isin loading position, neutralizes the tractor hydraulic system bystopping all oil flow in either line 22 or 23. When this occurs, thespring 114- forces the valve member 88 toward the right until it strikesthe slide pin 51 and stops in a position such that ports 113, 93, 11 and95 are interconnected by the groove 94 in valve member 88. The oil whichwas trapped between the valve member '88 and the slide pin 51 isdisposed of in two ways.

The majority of this oil passes through port 112 to spool 83. Becauseoil cannot pass to the right through valve 37 there is an increase inpressure which, acting on the bottom of spool 83 by way of passage 91,forces the spool 83 upwardly to close ports 116 and 117. After port 117is closed, any oil trapped above spool 83 is released by passing throughvalve 84 and restriction 82, thence to the line 22 and the sump. Any oilremaining between the valve member 88 and the slide pin 51 slowly passesback through the small axial hole 115 in valve member 88 to help fillthe space vacated by the valve member 88 as it moves to the right.

It is now assumed that the operator lowers the bucket 14 to the groundto fill it. For best operation, the entire machine will be tilted sothat the weight of the scoop will be resting on the bucket cutting edge118. Under ideal conditions, cutting edge 113 will immediately penetratethe material to be loaded, creating a counterclockwise torque on thebucket.

Because in actual operation, the bucket did not stop instantly when stoproller 41 dropped into depression 11%, there is a slight gap betweenroller 41 and the load stop abutment 42. When loading is commenced, thetorque mentioned above will cause the load stop abutment 42 to movetoward the stop roller 41, thus shortening cylinder 27 and extendingcylinder 28. Oil displaced from cylinder 27 passes through line 25,ports 95 and 93 to line 22. The only open port from line 22 is passage108 to a slide pin 50. Pressure on slide pin 50 stops any tendency itmay have to move to the left and thereby allow stop roller 41 todisengage the load stop abutment 42. The remaining volume of oildisplaced from cylinder 27 passes from the valve member 88 through theport and restriction 107 and into the passage 104. A considerable amountof pressure is required to open valve 85 so that the oil opens the valve100 instead and passes to cylinder 28 through line 26, through valve 80and through passages 71, 73 and 74 to provide the volume required bycylinder 28 as it extends.

In the event that the material to be loaded is very hard and the cuttingedge 118 cannot penetrate its surface,

there is a clockwise torque exerted on the bucket 14 because of itsweight resting on cutting edge 118. This causes cylinder 28 to attemptto contract by forcing oil up through passage 72 through valve 81 andthrough passage 71 to the line 26, but this is prevented by valve whichis closed. This action causes the scoop weight to continue to rest onthe cutting edge 118, thus aiding penetration.

When the bucket is filled it is assumed that it is raised by theoperator and tipped into carrying position. To do this, the operatorenergizes the tractor control valve 21 so that pressure is again appliedto line 22, and line 23 is again open to the sump. Because the spool 83is raised, ports 116 and 117 are closed and the only outlets are throughports 108, 113, 93 and through port and restriction 107. Pressureapplied through port 108 acts on slide pin 53 but causes no reaction.Pressure at ports 113 and 93 causes flow past the valve member 88through port 95 through passage 96, and thus causes the valve pin 98 tobe raised and valve ball 1% to be opened. Because of its restriction,only a very small amount of oil passes through port 137.

In addition, oil flows to cylinder 27 through line 25, through passages62 and 63 to extend the piston 30 and cause the bucket 14 to rotateclockwise. Stop roller 41 passes from the load-stop abutment 42 to thecarry-stop abutment 43. As stop roller 41 is passing over the carry stepabutment 43, the ring 55 of cylinder 28 is passing over land 61) of thethrottling plug 53. Oil trapped in this area can leave only through therestriction in line 72 and by valve 31 and through line 71, through therestriction caused by needle valve 77, down through line 73 and upthrough line 71, all of which brakes the rotation to a gentle stopagainst positive mechanical stops on the bucket. Safety valves in thetractor hydraulic system or possibly valve 102 opens to return oil tothe tractor sump until the operator again neutralizes the tractorhydraulic system.

When the stop roller 41 falls into the depression and engages carry stopabutment 43, the rock shaft 36 causes a corresponding adjustment offollowers 46 and 47 which causes a slight adjustment in position ofslide pin 51 andv of spool 38 so that ports and 107 are closed.

To empty the bucket, the operator energizes the tractor control valve 21to apply pressure to line 23 and to open line 22 to the sump.

When this is done, oil entering through line 23 opens valve 35 to forcethe spool 83 down as far as possible. A

small amount of oil continues to pass through valve 85, port 117 andrestriction 32 back to the line 22 and the sump. With the stop roller 41against carry-stop abutment 4-3, ports 1115 and 1117 are closed, but oilpassing;

from line 1614 through port 1% forces the valve member 83 and the slidepin 51 to the right rotating the follower 45 counterclockwise todisengage the stop roller 41 from the carry stop abutment 43, and hencefrees the bucket When the valve member 88 has moved a maximum amount tothe right, ports 105,-

to turn counterclockwise.

113, 1117, and 112 are closed While ports 93 and 95 are opened andconnected. The oil flowing through passage 1% passes through valve 1011,through line 26 to cylinder 23, through passage 71, valve 84 and lines73 and 74 to extend the piston 33, and hence rotate the bucketcounterclockwise.

As the follower 45 is rotated, the stop rollers 40 engage the plates 17,and as the bucket is rotated counter. clockwise, the rollers 41 rollover the abutments 43 and sages 62, 63 and 64 to line 25, throughpassage 96 of the sequence valve, through ports 95 and 93 to line 22 andback to the sump. As ring 64 of cylinder piston 30 passes over land 57of the throttling plug 52, there is no braking I [In action because ofthe relatively open set of needle valve 65. However, as the stop roller40 is passing over the dump stop abutment 44, ring 54 meets land 56, andthe oil trapped above ring 54 can pass only through valve 68 whichrestricts the flow to provide braking action.

As the stop roller 40 passes over the dump stop abutment 44, pressure isexerted through port 106 to valve 88, thus forcing valve member 88 andthe slide pin 51 to the right, rotating the valve follower 45counterclockwise and moving the stop roller 40 down to the right of thedump stop abutment 44 so as to lock the bucket 14. Any furthercounterclockwise rotation of bucket 14 is prevented by fixed mechanicalstops. Until the operator neutralizes the tractor hydraulic system, oilwill pass through the tractor safety valve 21 to the sump or throughline 23, valve 100 and valve 103, to line 25 and passage 96 back to thesump.

To return the bucket 14 to the loading position the tractor hydraulicsystem is energized to apply pressure to line 22 and to open line 23 tothe sump. The hydraulic system is now in practically the same state thatit was at the beginning of this explanation and the flow follows thesame passage.

As stop roller 41 approaches the load stop abutment 42, the ring 55 ofcylinder piston 33 will contact land 61. Oil trapped above ring 55cannot pass through passages 73 or 74 because of valve 80, and therestriction in passage 72 as well as valve 81 will restrict the flowthrough passage 71 and line 26, and so provide braking action to thebucket rotation.

Under some conditions it is desirable to reverse the bucket 14 so thatit can be loaded with the scoop moving to the right as viewed in FIG. 2.To accomplish this, the bucket can be removed from the scoop frame andcylinders 2728, by removing bolts 120 and 121 on one bucket end plate 17and bolts at 122 and 123 on the 0pposite bucket end plate. The bucket isthen turned about its vertical axis so that when in loading position,the cutting edge 118 is toward the right.

The hydraulic system is then adjusted as follows: Screw valve 66 ofcylinder 27 is closed and valve 70 is slightly opened. Screw valve7576-77 of cylinder 28 are all opened. Screw 101 on the sequence valve24 is closed to hold valve pin 98 up and valve ball 100 permanentlyopen.

Operation in reverse is much the same as forward operation except thatto obtain automatic stopping at the loading position, the bucket isrotated as far as possible counterclockwise to the carrying position andthen rotated clockwise. As stop roller 41 leaves the carry stop abutment43, it is forced into depression 111 which serves the same purpose forreverse operation as depression 110 does for forward operation, and atthis point bucket rotation will stop automatically. When loading isbegun oil flow from cylinder 28 will cause counterclockwise rotation ofthe valve follower 45 and force the stop roller 40 into engagement withthe load stop abutment 42.

The drawings of FIGS. 2, 3, 4 and 5 show all parts of the hydraulicsystem in the position they would assume when the bucket is rotatedclockwise into loading position and the roller 41 is moving just pastcarry stop abutment 43. Oil flows from the pump through the valve 21,through line 22 and into the sequence valve 24. As a result, the oilflows down through line 22, through port 93, by the reduced valveportion 94 formed in valve member 88, through port 95, and hence throughline 96 to the cylinder line and consequently to the cylinder 27. FromFIG. 4, it is seen that the oil pressure closes the valve 68 and the oilflows through passage 62 to cause the piston 30 to extend and rotate thebucket clockwise.

Clockwise rotation of the bucket 14 causes a retraction of piston 33 andcylinder 28, and thus causes a return flow through the passages 71, 72,73 and 74. This return oil flows through the line 26 into the sequencevalve 24 past the ball valve 100, and hence flows into passage 104 andis discharged into the sump through line 23.

Oil that is under pressure in line 22 flows through the restriction 108and exerts force against the slide pin 50 causing it to move to theright, as shown in FIG. 3, to rotate the valve follower 45 clockwise,and hence causing the stop roller 41 to move down into the depression111. Upon movement of stop roller 41 into the depression 111, the slidepin 59 is moved to the right (FIG. 3) forcing slide pin 51 and valvemember 83 to the extreme left end of the bore in which the valve member88 operates. Similar to the operation previously described, this actionof valve member 3% stops the flow of oil through passage i=6 to thecylinder 27 and stops the bucket 14 in the loading position. The entireoil flow through line 22 is now passing through port 113 to port 105,through passage 104 and hence back to the sump through line 23. Asstated previously the only exception is a small amount of oil :1 fromline 22 through valve member 87, to port through the small passage 115,through port 106 back to the sump, and a small amount of oil passingthrough port 167 and back to the sump.

At this point, the operator neutralizes the hydraulic system by stoppingall oil flow in either line 22 or 23. When this occurs, the spring 114forces the valve member 38 toward the right until it strikes the slidepin 51 and stops in a position such that ports 113, 93, 107 and areinterconnected by the groove 94 in valve member 88.

The operator now lowers the bucket to the ground to fill it. Because inoperation, the bucket stopped in depression 111, there is a slight gapbetween roller 41 and the load stop abutment 42. When loading iscommenced the torque will cause the load stop abutment 42 to moveclockwise. Oil from cylinder 28 flowing back into the sequence valve 24causes a pressure on slide pin 51 that rotates the follower 45counterclockwise and forces the stop roller 45) into engagement with theload stop abutment 42.

Although the invention has been described by making detailed referenceto a single preferred embodiment, such detail is to be understood in aninstructive, rather than in any restrictive sense, many variants beingpossible within the scope of the claims hereunto appended.

We claim as our invention:

1. A scoop for an implement comprising a frame, a bucket pivotallymounted on said frame, hydraulic means operatively connected to saidbucket for rotating the bucket about the pivot axis of said bucket,valve means connected to said hydraulic means for controlling operation,the bucket being provided with stop abutments spaced about the pivotaxis of said bucket, a shaft rotatively mounted on said frame, stopelements attached to said shaft and selectively engaging said spacedabutments in predetermined positions upon rotation of the bucket aboutits pivot axis, and means operatively interconnecting said shaft andsaid valve means for controlling operation of said stop elements, saidvalve means causing the hydraulic means to retain the bucket selectivelyin said predetermined positions upon engagement of said stop elementsselectively with said abutments.

2. A scoop for an implement comprising a frame, a bucket pivotallymounted on said frame, hydraulic means operatively connected to saidbucket for rotating the bucket about the pivot axis of said bucket,valve means connected to said hydraulic means for controlling operation,stop means on the bucket spaced about the pivot axis of said bucket, ashaft rotatively mounted on the frame, a follower attached to the shaftand operatively connected to the valve means for actuation of the shaft,and means operatively interconnecting the shaft selectively with thespaced stop means in predetermined positions upon rotation of saidbucket about its pivot axis, the valve means causing the hydraulic meansto retain the bucket selectively in said predetermined positions.

3. A scoop for an implement comprising a frame, a bucket pivotallymounted on said frame, hydraulic means operatively connected to saidbucket for rotating the bucket about the pivot axis of said bucket,valve means connected to said hydraulic means for controlling operation, the bucket being provided with stop abutments spaced about thepivot axis said bucket, a shaft rotatively mounted on said frame, stopelements attached to said shaft, one or the other of said stop elementsselectively engaging said abutments in predetermined positions uponrotation of the bucket about its pivot axis, a follower attached to theshaft and operatively connected to the valve means for actuation of theshaft and said stop elements, said valve means causing said hydraulicmeans to retain said bucket selectively in said predetermined positionsupon engagement of the stop elements selectively with said abutments.

4-. A scoop for an implement comprising a frame, a bucket pivotallymounted on said frame, a hydraulic means including a cylinder connectedbetween the frame and each end of the bucket, one cylinder beingconnected to and acting on one side of the pivotal axis of the bucket,and the other cylinder connected to and acting on the opposite side ofthe bucket axis, valve means connected to said hydraulic means forcontrolling operation, stop means mounted on the frame and engaging thebucket in predetermined positions, and means operatively interconnectingthe stop means and valve means for controlling operation of said stopmeans, said hydraulic means rotating said bucket to said predeterminedpositions, said valve means causing said hydraulic means to retain thebucket selectively in said predetermined positions.

5. The combination and arrangement of elements as recited above in claim4, but further characterized in that said hydraulic cylinders includehydraulic passages having valve elements for selectively opening andclosing the passages for braking the rotative action of the bucket inone limitof each cylinder operation.

6. A scoop for an implement comprising a frame, a bucket pivotallymounted on said frame, hydraulic means operatively connected to saidbucket for rotating the bucket about the pivot axis of said bucket todifferent predetermined positions, valve means connected to saidhydraulic means for controlling operation, the bucket having itsperiphery provided with a plurality of stop abutments spaced about thepivot axis of said bucket, stop means mounted on the frame and engagingthe periphery of said bucket and selectively engaging said stopabutments in said predetermined positions upon rotation of the bucket,and means operatively interconnecting said stop means and said valvemeans for controlling operation of said stop means, the valve meansbeing conditioned upon engagement of said stop means selectively withsaid stop abutments so that said hydraulic means retains said bucket ineach of said predetermined positions.

7. A scoop for an implement comprising a frame, a bucket pivotallymounted on said frame, hydraulic means operatively connected to saidbucket for rotating the bucket about the pivot axis of said bucket,valve means connected to said hydraulic means for controlling operation,the bucket being provided with a plurality of stop abutments spacedabout the pivot axis of said bucket, a rock shaft rotatively mounted onsaid frame, stop members attached to said rock shaft, and meansoperatively interconnecting said rock shaft and said valve means to moveone or the other of said stop members selectively into engagement withsaid stop abutments in predetermined positions of the bucket uponrotation of the bucket about its pivot axis, the valve means beingconditioned upon engagement of said stop members selectively with saidstop abutments so that said hydraulic means retains said bucket in saidpredetermined positions.

8. The combination and arrangement of elements as recited above in claim7, but further characterized in that said stop members consist of aU-shaped arm extending outwardly from said rock shaft, one end or theother of said U-shaped arm engaging the periphery of the bucket andselectively engaging the said stop abutments.

9. The combination and arrangement of elements as recited above in claim7, but further characterized in that lb the said means interconnectingthe rock shaft and said valve means includes a follower attached to saidrock shaft and extending on opposite sides of said shaft, and valveelements engageable by said follower and operable by said valve means,the follower oscillating said rock shaft in response to the valve means.

10. A scoop for an implement comprising a frame, a bucket pivotallymounted on said frame, hydraulic means operatively connected to saidbucket for rotating the bucket about the pivot axis of said bucket,valve means connected to said hydraulic means for controlling operation,the bucket including opposite end members each provided withperipherally spaced stop abutments about the pivot axis of the bucket, arock shaft rotatively mounted on said frame and extending along saidbucket, each end of the rock shaft having a plurality of stop r embers,one or the other of said stop members engaging the bucket periphery, afollower attached to said rock shaft, and valve elements engageable bysaid follower and operable by said valve means, the follower oscillatingsaid rock shaft in response to the valve means so as to move one or theother of said stop members at each end of the shaft selectively intoengagement with said stop abutments in predetermined positions of thebucket upon rotation of the bucket about its pivot axis, the valve meansbeing conditioned upon engagement of the stop members selectively withsaid stop abutments so that said hydraulic means retains the bucket insaid predetermined positions.

11. A scoop for an implement comprising a frame, a bucket pivotallymounted on said frame, hydraulic means operatively connected to saidbucket for rotating the bucket about the pivot axis of said bucket tovarious desired positions, valve means connected to said hydraulic meansfor controlling operation, the bucket being provided with a plurality ofstop abutments spaced about its periphery and about its pivot axis, arock shaft rotatively mounted on said frame, stop members attached tosaid rock shaft, said stop members consisting of a U-shaped armextending outwardly of said rock shaft, one end or the other of saidU-shaped arm selectively engaging the periphery of the bucket, afollower consisting of a U-shaped arm attached to and extendingoutwardly from said rock shaft, valve elements engageable by saidfollower and operable by said valve means, the follower oscillating saidrock shaft in response to the valve'means so as to actuate said stopmembers selectively into engagement with said stop abutments inpredetermined positions of the bucket upon rotation of the bucket aboutits pivot axis, the valve means beingconditioned upon engagement of thestop members selectively with said stop abutments so that the hydaulicmeans retains the bucket in said predetermined positions.

12. A scoop for an implement comprising a frame, a bucket pivotallymounted on said frame, hydraulic means operatively connected to saidbucket for rotating the bucket about the pivot axis of said bucket tovarious desired positions, valve means connected to said hydraulic meansfor controlling operation, the bucket including opposite end portionseach provided with peripherally spaced stop abutments about the pivotaxis of said bucket,

a shaft extending along said bucket and rotatively mounted on saidframe, stop members consisting of a U-shaped arm attached to andextending outwardly from said shaft, one end or the other of saidU-shaped arms of said stop members selectively engaging the periphery ofthe bucket, a follower consisting of a U-shaped arm attached to andextending outwardly from opposite sides of said shaft, valve elementsengageable by said ends of the U-shaped arm of the follower and operableby said valve means, the follower oscillating said shaft in response tothe valve means so as to bring the ends of the U-shaped arms of the stopmembers selectively into engagement with said stop abutments inpredetermined positions of the bucket upon rotation of the bucket aboutits pivot axis, the valve means being conditioned upon engagement of thestop members selectively with said stop abutments 11 so that thehydraulic means retains the bucket in said predetermined positions.

13. A scoop for an implement comprising a frame, a bucket pivotallymounted on said frame, the bucket being provided with a plurality ofstop abutments spaced about the pivot axis of said bucket, a shaftrotatively mounted on said frame, stop members attached to said shaftand adapted selectively to engage the stop abutments in predeterminedpositions of the bucket, hydraulic means operatively connected to saidbucket for rotating the bucket about the pivot axis of said bucket,valve means connected to said hydraulic means for controlling operation,the valve means including a pair of slide pins one on each side of saidshaft, follower means attached to each side of the shaft and engagingsaid pins upon oscillation of said shaft so as to actuate said valvemeans upon engagement of the stop members selectively with said stopabutments so that the hydraulic means retains the bucket in saidpredetermined positions, and the valve means including means foroperating said pins to cause operative engagement of the stop membersselectively with the stop abutments in the predetermined positions ofthe bucket.

14. A scoop for an implement comprising a frame, a bucket pivotallymounted on said frame, the bucket being provided with a plurality ofstop abutments, a shaft rotatively mounted on said frame, stop membersattached to said shaft and selectively engaging the stop abutments inpredetermined positions of the bucket, hydraulic means operativelyconnected to said bucket for rotating the bucket, valve means connectedto said hydraulic means for controlling operation, control means havinga pair of hydraulic lines to said valve means, the valve means includinga pair of slide pins, follower means attached to the shaft and engagingsaid slide pins for shaft actuation, a valve member adapted to engagethe first of said pins and adapted to control flow to said hydraulicmeans, means for exerting hydraulic pressure on the second pin upon feedthrough one line so as to bring one of said stop members against oneabutment in a predetermined load position of said bucket, and means forexerting hydraulic pressure against the valve member and said first pinupon feed through the other said line so as to bring another said stopmember against another said abutment in a predetermined dump position ofsaid bucket, the valve means causing said hydraulic means to retain saidbucket in said load and dump positions.

15. The combination and arrangement of elements as recited above inclaim 14, but further characterized in that the said valve meansincludes means for moving the valve member away from the said firstslide pin to stop flow to the hydraulic means after the bucket has beenrotated to the load position, resilient means urging the valve memberagainst the said first slide pin upon stopping of hydraulic feed toreopen the flow passage to the hydraulic means, and the said means forexerting hydrau lic pressure against the said second slide pin upon feedthrough the said one line causing the stop member to engage another saidstop abutment as the bucket is rotated to another position by thehydraulic means upon resuming hydraulic feed through the said same line,the valve means causing said hydraulic means to retain said bucket inthe last said position.

16. A scoop for an implement comprising a frame, a bucket pivotallymounted on said frame, the bucket being provided with a plurality ofstop abutments spaced about the pivot axis of said bucket, a shaftrotatively mounted on said frame, stop members attached to said shaftand selectively engaging the stop abutments in predetermined positionsof the bucket, hydraulic means operatively connected to said bucket forrotating the bucket about the pivot axis of said bucket, valve meansconnected to said hydraulic means for controlling operation, the valvemeans including a pair of slide pins, follower means attached to theshaft and engaging said pins for actuation of said valve means uponengagement of the stop members selectively with said stop abutments, thevalve means including means for operating said hydraulic means in apredetermined sequence to rotate the bucket about the pivot axis of saidbucket from loadto-carry-to-dump positions and to retain said bucket insaid positions, the valve means including means for actuating said slidepins hydraulically so as to operate said follower means and causeoperative engagement of the stop members selectively with the stopabutments in the different positions of said bucket.

References Cited in the file of this patent UNITED STATES PATENTS2,008,178 Harrison July 16, 1935 2,196,690 Barrett Apr. 9, 19402,293,636 Berner et a1 Aug. 18, 1942 2,445,260 Brimhall July 13, 19482,463,675 Beyerstedt Mar. 8, 1949 2,488,699 Anthony Nov. 22, 19492,760,284 Cook Aug. 28, 1956

